A fluorescent lamp (FL) is highly efficient in emitting light. To use the FL lamp instead of a incandescent lamp, the FL lamp is made small. To insert a small fluorescent lamp or the like into a bulb socket of the incandescent lamp the lamp apparatus size, including an electronic ballast, must be further reduced.
FIG. 1 shows a conventional compact fluorescent lamp apparatus having a ballast case 22 without a compact fluorescent lamp socket, a small fluorescent lamp 23 and a bulb base 21, which are integrated in one unit.
Although the lamp apparatus is convenient to use, the integral unit, including both the socket and ballast, must be replaced with a new one when a life of a fluorescent lamp is ended. Thus, the combination ballast and bulb unit wastes material sources i.e., a prefectly usable ballast is discarded when the fluorescent lamp is no longer operational.
A compact fluorescent lamp shown in FIG. 2 has been commercially available. The compact fluorescent lamp has a plug 28 that can be fitted to a socket in a socket-type ballast, and four pins 29 for electric connection.
To use such a compact fluorescent lamp, many types of ballast are produced. One such type of electronic ballast has a socket for accommodating the compact fluorescent lamp plug, 28 and an incandescent bulb base for fitting in to an incandescent bulb socket.
However, further reductions in the it of the conventional electronic ballast having a compact fluorescent lamp socket and a bulb base are needed.